Inclusion complexes of β-cyclodextrin with chlorogenic acids (CHAs) from crude and purified aqueous extracts of green Robusta coffee beans (Coffea canephora L.)

- Green coffee extract was purified by the centrifugal partition chromatography method.
- Inclusion complexes of chlorogenic acids (CHA) with β-CD were confirmed by ESI-MS/MS.
- High antioxidant activity of CHA was maintained after inclusion complexation.

The initial aim of the study was to purify the crude aqueous coffee bean extract, containing CHAs and caffeine with the use of the centrifugal partition chromatography (CPC) technique to obtain a higher concentration of CHAs with a simultaneous decrease of caffeine quantity. As a result of extract purification CHA content was increased by about 50% and caffeine was completely eliminated. CHAs were identified by the LC-ESI-MS/MS technique. A further aim was to obtain inclusion complexes of both crude and purified extracts with β-cyclodextrin (β-CD). The highest obtained concentration of CHAs in a complex with β-CD amounted to 19 g/100 g. The formation of inclusion complexes was confirmed with the use of ESI-MS/MS and differential scanning calorimetry (DSC) techniques. The analysis of antioxidant capacity of inclusion complexes with β-CD revealed that crude and purified extracts showed about 2-fold higher antioxidant capacity than the obtained complex.